Electric heater



(No Model.)

0. H. TALMAGE. ELECTRIC HEATER.

No. 440,071. Patented Noml, 1890.

ELQI A5,. a /y I H 1 1;: 023, at d r zexzfi Imag UNITED STATES PATENT OFFICE.

CHARLES H. TALMAGE, OF KANSAS CITY, MISSOURI.

ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 440,071, dated November 4, 1890.

Application filed November 23, 1889. Serial No. 331,337. (No model.)

To all whom it may concern.-

Be it known that 1, CHARLES H. TALMAGE, of Kansas City, in the county of Jackson and State of Missouri, have invented a certain new and useful Improvement in Electric Heaters, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

My invention consists in an alternating current-transformer, constructed to act also as a heater with the primary coil surrounding an inner core that is composed of concentric cylinders of thin sheet metal and intervening longitudinal wires or rods and concentric cylinders of similar materialoutside the primary coil in which the secondary current is induced, and which radiate the heat induced by the currents of electricity. The primary coil is formed in sections, more or less of which may be thrown into circuit to regulate the amount of heat produced. The cylinders and rods, both inside and outside the primary coil, are considered as the core, thus making a closed magnetic circuit.

Figure I is alongitudinal section of a cooking stove or range with my improvement applied thereto. Fig. II is an end View of the heater. Fig. III is a side view of the heater, part broken away and part in longitudinal section. Fig. IV is an end view showing the heater in somewhat modified form. Fig. V is a section showing the heater applied to a water-tank for heating a railway-car, &c. Fig. VI is a diagram showing a thermostatic switch in connection with my heater.

The core 1 of the heater is formed of concentric cylinders 2, formed preferably of very thin sheet metal, kept in proper relative position by soft-iron wires 3, interposed between them, the obvious object of said core 1 being to strengthen the magnetic field. Around the outer one of the interior core-cylinders 2 is wound the primary coil 5 of insulated wire, preferably of copper. This coil is made in two or more sections, as 6, 7, and 8, more or less of which may be thrown in circuit to increase or diminish the resistance of the coil. The ends of the coil-section 6 are shown in conducting-wires 6' and 6 the ends of the coil-section 7 in conducting-wires 7 and 7 and the ends of the coil-section 8 in conducting-wires 8 and S The outer core of the heater has a construction similar to the inner core, being composed of concentric cylinders 9 of thin sheet metal separated and held in position by interposed wires or rods 10 of soft iron or other suitable material, which strengthen the magnetic field and pcrmit'the heat to radiate by afiording a draft between 'the surfaces of the cylinders.

11 are clamps, which extend radially from the interior of the inner core-cylinder 2 to the outside of the outer cylinder 9, and are bent at right angles at each end to engage over the edges of the cylinders, as shown in Figs. III and IV. For these clamps may be substituted a perforated top, the perforations being radial, the construction being tantamount to the connection of all the clamps by a band of iron on the outside and inside circumference.

If only a moderate amount of heat is wanted, all the primary coil-sections 6, 7, and 8 are thrown in serial circuit, while if a larger amount of heat is required one or more of the sections are cut out, thus lessening the resistance and proportionally increasing the current. As the electro-motive force in the secondary coil depends on the ratio between the number of turns in the primary and secondary coils and the relative resistance of the same, it is obvious that when the proportion is one hundred to one there will be twice the electro-motive force in secondary coil as when it is two hundred to one, and this double e1ectro-motive force in secondary circuit will double the electric current through the second circuit, whose resistance is constant, thus giving four times the amount of heat, and thus the amount of heat produced may be increased or diminished, as aforesaid.

The heater may be used with a constant current by means of a current breaker or reverser of any suitable construction.

In Fig. IV is shown a construction of my heater adapted for use in large rooms. The

elliptical cylinders 9', of thin sheet metal, being put on as protectors, as well as extra radiating-surfaces.

In Fig. I the heater is shown in a cookingrange, in which 12 are cooking-ovens and 13 ICO . shown.

The primary current may pass through a thermostat 16, as seen in Fig. VI, which is placed in the room to be heated and arranged to break circuit on the temperature reaching a given point.

In Fig. V the device is shown applied to the heating of water or other fluid in a closed tank 17, with which may be connected a system of heating-pipes. V

It will be seen that the heat will be radiated from both the inner and outer sides of the cylinders in which the secondary current is induced.

I claim as my invention 1. An electric heater consisting of a transformer having a primary coil and aclosed secondary circuit of sheet-metal cylinders surrounding the primary coil, whereby a current of electricity of moderately high electro-motive force can be transformed into a heatingcurrent, substantially as herein described.

2. An electric heater consisting of a transformer having a primary coil and a closed secondarycircuit, of sheet-metal cylinders surrounding the primary coil, said sheet-metal cylinders being separated by metal rods or wires, whereby the induced current is conducted circumferentially, the magnetic lines of force being at right angles thereto, and the heat radiated from the surfaces, substantially as herein described.

3. An electric heater consisting of a converter, a primary coil, and a secondary coil, said secondary coil being formed of broad and thin sheet-metal cylinders, whereby the heat produced by the induced current is radiated for heating purposes, substantially as herein set forth.

4. In an electric heater, the combination of the core formed of concentric sheetmetal cylinders and the primary coil surrounding said core, with the secondary coil formed of concentric cylinders adapted to carry the induced currents and radiate the heat thereby generated, substantially as herein set forth.

5. In an electric heater, the combination of the core composed of sheet-metal cylinders and interposed rods and the primary coil surrounding said core, with the secondary coil formed of concentric cylinders, substantially as herein set forth.

6. In an electric heater, the combination of the primary coil properly insulated and a series of sheet-metal cylinders arranged inside and outside of said coil, with interposed metal rods separating the inner cylinders for forming the core, and interposed metal rods separating the outer cylinders for forming the secondary circuit and heat-radiatin g coil, substantially as herein set forth.

CHARLES H. TALMAGE.

In presence of- SCOTT ASHTON, JOS. S. BROOKS. 

